Journal of Chemical Physics vol:107 issue:19 pages:8201-8203
Second-harmonic generation from Langmuir-Blodgett films of a polythiophene is strongly influenced by the chirality of the polymer. The polarization dependence of the process cannot be explained in the electric-dipole approximation. Evidence of contributions beyond electric dipoles is obtained directly from individual second-harmonic signals. (C) 1997 American Institute of Physics.